might not have been made, or if made, whether
they have been adopted.

Next we find the composition of rays or
beams proceeding from the sun and reflected
from the earth, or terrestrial objects, and the
decomposition of such rays, alluded to as an
obscure subject. There is abundant room for
experiment and discovery here also, for the
pursuer of natural science, for the exact
composition of bundles of the sun's rays is still
an obscure subject.

The effects of extreme cold on different liquids,
congealing certain parts and separating out
portions having peculiar properties, is referred to
as an unexplained phenomenon, and the
peculiar thin oil thus obtained from freezing common
oils, is particularly mentioned. There is much
to be learnt still about the physical properties
of extreme cold in producing a kind of partial
decomposition, or, at least, a separation of
compound substances hardly otherwise attainable;
bul the derivation of thin, and unchanging oils
from the common kinds is still a subject under
experiment.

Our philosopher adds, "It would be not only
tedious bul, almost endless to prosecute those
instances that might be afforded by other more
general and operative states and faculties of
bodies. For not only motion and rest, fluidity
and firmness, gravity and the like, have a more
universal influence of natural things than even
philosophers are wont to take notice of, but
those less catholic affections of matter that are
reckoned among but particular qualities, such as
gravity and heat, may have so diffused an
influence, and be applicable to so many differing
purposes, that I doubt whether all the uses of
that particular degree or pitch of heat that
reigns in fire, will have all its uses discovered
before the last great fire shall dissolve the frame
of nature."

Boyle next considers that  " external objects
having certain mutual relations specially adapting
them to each other and to human requirements,"
there may hereafter be found many more
such relations than are now suspected. He
illustrates this by the case of a lock and key,
remarking that if either were existing by itself
it could have no value, but if at any time the
corresponding part were found, the use would
be manifest. As special examples, he mentions
the peculiar use of steel in the composition of a
permanent magnetic needle, the peculiar uses of
what is called sugar of lead, prepared by the
action of common vinegar on metallic lead, the
preparation of ammonia from animal offal, the
uses of metallic oxides and salts for colouring
glass and porcelain, the effect of particular
colours on the temper and nervous irritability of
certain animals, and many others.  In all these
cases the lock, represented by the natural
compound substance or the result, has to be opened
by the human contrivance, a key or explanation
—itself an artificial construction—before we can
obtain a satisfactory result.

This view of men's ignorance of the uses of
natural things is illustrated further in modern
times by the numberless discoveries and
applications that have been made since the days of
Boyle, and that are constantly being made in
almost every department of science, but perhaps
more especially in chemistry and physics. Who,
for example, could have expected that one
important use of part of the rays that form a beam
of light would be to produce a permanent image
of any object presented to a surface prepared in
a particular way. Certainly the marvels of photography
exceed all that had been discovered when
these essays were written, but their causes are
not yet understood—hardly even suspected. Or
who could have imagined that by the insulation
of a copper wire with gutta percha, such wire
could be safely passed through, and left at the
bottom of deep water, and there conduct the
electric fluid from one shore to another, remaining
under the absolute control of the electrician
at either end, who can pass a current through
the wire or stop it at pleasure?

But it is needless to point out to the reader
the numerous instances in which this peculiar
fitness of certain things, existing in nature or
prepared by man, comes in as the key to open
the lock, and enable man to make use of the
mysterious powers of nature and adapt nature
to his own purposes.

Other examples of men's previous ignorance
in the uses of natural things are seen when
altogether new and unexpected properties are found
by combining together, for the obtaining of a
useful result, various substances long employed
for other purposes, and having properties
altogether distinct. Here, again, so much has
already been done that we may well suppose
much yet remains to be discovered. Thus, by
mixing tin, which is not at all sonorous, with
copper, which is not much more so, we obtain
an alloy which, when cast into bells, is harder,
and wonderfully more sonorous than either. Or
as a very simple but complete illustration, who
could have anticipated the production of a salt
by mixing an acid with an alkali, or of glass by
melting sand with soda?

A fourth illustration of the subject is obtained
by considering how often we discover altogether
distinct uses of substances when they are
prepared in some way different from that generally
adopted. Thus, iron, by the help of fire and
water, may be adapted for various purposes,
some requiring hardness with brittleness, some
toughness, some temper, and other qualities.
The various uses of paper for picture-frames,
embossed work, and furniture, are instances
given by Boyle under this head, and he describes
a method of preparation for these results. The
use of the shreds of leather for making glue, the
manufacture of ivory black from ivory and of
the fine membrane prepared from the intestines
of the ox—"all these," says Boyle, "are such
as either nature herself, or nature assisted by
tradesmen, has presented us."  And, therefore,
questionless, the power that a skilful management
may have to produce great changes in
bodies and thereby fit them for new uses, will
be much advanced when they shall be ordered